1. Field of the Invention
The present invention relates to methods and apparatus for locating a predetermined position in a computer file and more particularly to such methods and apparatus in which a scroll box is moved to locate and display a position in the file.
2. Description of the Related Art
In a Holter ECG monitoring system, a patient is fitted with a monitor which detects and stores continuous ECG waveforms. Sometimes several leads are connected to the patient so that two or more such waveforms are recorded. It is not unusual for such a monitor to be worn for many hours thereby generating thousands of periodic heartbeat waveforms which are stored for later review to assist in diagnosis and treatment of the patient.
Scroll boxes are commonly used for locating and displaying a portion of a file in windowing programs such as Microsoft Windows.TM. and MOTIF.TM.. A scroll bar indicates the possible area to be viewed and a scroll box positioned on the scroll bar indicates the position of that portion of the file in the window relative to total file length. In a word processing program if the scroll box is halfway down the scroll bar it indicates that the screen is displaying a portion from approximately the middle of the document. An operator uses a mouse to position a cursor on the scroll box, depresses a button on the mouse, and moves the mouse thereby moving the scroll box so long as the mouse button is depressed. Such mouse movement moves the box relative to the scroll bar. When the mouse button is released, a new portion of the file corresponding to the new scroll box position is displayed in the window.
The difficulty with this totally qualitative approach is that the user often bumbles around, successively approximating position in the file and then paging up or down to find an exact position. This often requires the user to take a stab at the position using the scroll box, look for a frame of reference (document contents, time, etc.) and then correct the selection. Another alternative to this is a Go to function often found in applications. The user selects Go to and a new scroll box appears. The user has an exact position readout (in, e.g., pages or time) available as the scroll box moves along a scroll bar. However, the user must be fairly dexterous to move the box accurately while observing the time displayed, especially when the box is not directly under the time readout.